• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.9
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• pp.4220-4241
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• 2017

For the downlink energy-harvesting small cell network, this paper proposes an interference management algorithm based on distributed coalitional game. The cooperative interference management problem of the energy-harvesting small cells is modeled as a coalitional game with transfer utility. Based on the energy harvesting strategy of the small cells, the time sharing mode of the small cells in the same coalition is determined, and an optimization model is constructed to maximize the total system rate of the energy-harvesting small cells. Using the distributed algorithm for coalition formation proposed in this paper, the stable coalition structure, optimal time sharing strategy and optimal power distribution are found to maximize the total utility of the small cell system. The performance of the proposed algorithm is discussed and analyzed finally, and it is proved that this algorithm can converge to a stable coalition structure with reasonable complexity. The simulations show that the total system rate of the proposed algorithm is superior to that of the non-cooperative algorithm in the case of dense deployment of small cells, and the proposed algorithm can converge quickly.

• Journal of the Korean Society of Earth Science Education
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• v.2 no.1
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• pp.41-47
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• 2009

This study examined the difference for the ability of self-directed learning and information literacy(the ability to use information) between small group-cooperative instruction of ICT practical environment and explanatory instruction using ICT of general classroom in middle school science education. The 138 students(7th grade) participated in this study were classified in two group, experimental group(68) and controlled group(70). Experimental small group consisted of 5-6 students who had different levels and the ability of each the group was equal. The teaching of experimental group was made in the science lab which was equipped with computers to connect super high-speed Internet. The teaching of control group was made in general classroom. Under these two environment, this study was executed during 10 weeks. As the result, Small group-cooperative learning using ICT was more effective in diminishing the gap of information literacy in middle school students. And in the ability of self-directed learning, the small group learning using ICT was also more effective than general classroom instruction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.611-627
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• 2017

For enhancing the coverage of wireless networks and increasing the spectrum efficiency, small cell networks (SCNs) are considered to be one of the most prospective schemes. Most of the existing literature on resource allocation among non-cooperative small cell base stations (SBSs) has widely drawn close attention and there are only a small number of the cooperative ideas in SCNs. Based on the motivation, we further investigate the cooperative approach, which is formulated as a coalition formation game with power control algorithm (CFG-PC). First, we formulate the downlink sub-channel resource allocation problem in an SCN as a coalition formation game. Pareto order and utilitarian order are applied to form coalitions respectively. Second, to achieve more availability and efficiency power assignment, we expand and solve the power control using particle swarm optimization (PSO). Finally, with our proposed algorithm, each SBS can cooperatively work and eventually converge to a stable SBS partition. As far as the transmit rate of per SBS and the system rate are concerned respectively, simulation results indicate that our proposed CFG-PC has a significant advantage, relative to a classical coalition formation algorithm and the non-cooperative case.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.05a
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• pp.122-122
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• 2007

• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.809-817
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• 2009

We call a cycle C be a small cycle if the length of C equals to 3 or 4. In this paper, we obtain two sufficient conditions to ensure the existence of vertex-disjoint small cycles in graph and propose several problems.

• Journal of Gastric Cancer
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• v.10 no.3
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• pp.137-140
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• 2010

Gastrointestinal stromal tumors (GISTs) constitute the most common primary mesenchymal tumors of the digestive tract and characteristically express c-kit (CD117). GISTs are the most common non-epithelial tumor of the GI tract and frequently originate from the stomach and small bowel. Specifically, the synchronous occurrence of a GIST with other epithelial tumors is rarely reported. Recently, we discovered one case of a concurrent gastric cancer and a small bowel GIST that was initially suspected to be peritoneal seeding from gastric cancer. The patient was initially admitted with epigastric pain. Gastric cancer with peritoneal seeding was suspected after an evaluation. Following a laparoscopic examination, a distal gastrectomy with D2 lymph node dissection and small-intestine segmental resection was performed. The final pathologic diagnosis was early gastric cancer and high-risk small bowel GIST. The patient refused adjuvant therapy for the GIST, and currently shows no other marked indisposition. He has been disease-free for 14 months.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.1
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• pp.222-236
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• 2019

Wireless content caching in small cell networks has recently been considered as a promising way to alleviate the congestion of the backhaul in emerging heterogenous cellular network. However, how to select files which are cached in SBSs and how to make SBSs work together is an important issue for cooperative cache research for the propose of reducing file download time. In this paper, a Cooperative-Greedy strategy (CGS) among cache-enabled small base stations (SBSs) in small cell network is proposed, in order to minimize the download time of files. This problem is formulated as a Chinese restaurant game.Using this game model, we can configure file caching schemes based on file popularity and the spectrum resources allocated to several adjacent SBSs. Both the existence and uniquencess of a Nash equilibrium are proved. In the theoretical analysis section, SBSs cooperate with each other in order to cache popular files as many as possible near UEs. Simulation results show that the CGS scheme outperforms other schemes in terms of the file-download time.

• Journal of the Korean Society of School Health
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• v.28 no.2
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• pp.67-78
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• 2015

The purpose of the study was to present a model of WHO Health Promoting School easily applicable to small-sized schools in rural areas. Methods: The study analyzed data of 11 small-sized schools in rural areas selected from 85 health promoting schools, an initiative led by the Ministry of Education from 2012 to 2014. Results: Through the analysis, the study found out the operation process of health promoting schools consists of five stages: system development, needs survey & survey on current status, school health policy development, program development & execution, and evaluation. In addition, the study was able to discover three key factors in operating health promoting schools: connection with curriculum, connection with community, and consensus among members. While it turned out the schools were following operation manuals faithfully, the biggest problem with operation was that the stages of needs survey, priority setting, and core task development were not closely coordinated. Conclusion: Although the model suggested in the study fails to reflect the characteristics of small-sized schools in rural areas, it is close to a universal model which could serve as a guideline when regular schools adopt the system of health promoting schools.

• 대한공업교육학회지
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• v.33 no.2
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• pp.72-96
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• 2008

This study was done through survey of the school and the small and medium enterprise which participated in "Human resources development program of small and medium enterprise technical high school's customized link", and we researched the problem with the actual condition of the program operation and analyzed the results of them. The analysis results are as follows. Firstly, the teachers recognized the purpose of this program operation as the activation of the occupation education between school and job world, On the other hand, people in charge of the company recognized the purpose of this program operation as the professional human resources supply to the small and medium enterprises. Secondly, the teachers perceived that the students' performative competence had improved through the operation of this program, while the inducement of some excellent students was not always available. Finally people in charge of the company responded that this program was helpful for the manpower guarantee, the profits of the company, the enhancement of the performative competence and adaptability of the high school graduates, and the cooperation of the technical high school and the company. However, they admitted that this program lacked the maintenance and repairing competence of the utilities, ability of grasping problems and the problem-solving skills, and the competence of the functional expertise of the high school graduates. Generally, the teachers of technical high school and people in charge of the company which participate in "Human resources program of small and medium enterprise technical high school's customized link" expressed positive appreciation for efficient management and potential development of this program.

• Journal of the Korean Society of Earth Science Education
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• v.4 no.1
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• pp.43-56
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• 2011

The purpose of this study is to examine the effects of small group inquiry skills on improving science process skills and attitudes toward science in elementary school science. The research questions of this study were as follows. First, effects of small group inquiry skills on improving science process skills in elementary school science. Second, effects of small group inquiry skills on improving attitudes toward science in elementary school science. The subjects of this study is two classes from 6th grade elementary classes in Busan. The experiment class practiced small group inquiry skills, while the control class practiced self inquiry. To verify the effect of the experiment, ANOVA was conducted. The main findings of this study are as follows. First, the small group inquiry skills gave a significant influence on increasing the science process skills, including the basic science process skills and the integrated science process skills, of students. Especially, among subordinate factors of science process skills between groups, it was effective to increase abilities of observing, reasoning, interpreting data, formulating hypothesis. It is necessary for teachers to make an effort to teach according to steps of the small group inquiry skills and to support inquiry activities, in order to increasing the science process skills. However, frequency of additional lessons have a little influence on increasing the science process skills. Second, there is meaningful change in the attitudes toward science for those who studied the small group inquiry skills. Also, they affected subordinate factors of the attitudes toward science, like the attitudes toward science inquiry, the happiness about science class. This study shows that the small group inquiry skills give a positive influence on the science process skills and attitudes toward science in elementary school science.